The invention relates to an apparatus for the production of carbon black. The apparatus has a cylindrical or parallelepipedic reactor with a reaction chamber for carbon black formation. In the cover of the chamber there are provided a plurality of feed units for the metered supply of air from an air heating apparatus and of hydrocarbons from a preparation apparatus. On the discharge side of the reactor heat exchangers are provided for reducing the temperature of the waste of flue gases leaving the reactor and the produced carbon black. In a filter unit arranged behind the heat exchanger the carbon black is separated from the waste or flue gases.
Various designs of carbon black production apparatus are known. In one known type, fuel gases are produced separately in a reactor and are mixed with hydrocarbons sprayed in at a different part of the reactor for initiating the reaction processes. The decomposition of hydrocarbons and the formation of carbon black starts to a limited extent at temperatures of 700.degree. to 800.degree. C. (degrees Celsius) and reaches its optimum level at between approximately 1100.degree. and 1400.degree. C., depending on the desired carbon black quality.
Variants of this known type, in which fuel gases are introduced into the reactor separately from the hydrocarbons are known, and those variants particularly relate to the arrangement of the burner heads for producing the fuel gases and the nozzles for introducing the hydrocarbons for carbon black production. Furthermore, an additional carrier gas is added. In addition, for temperature control purposes, water is added in various ways, although this reduces the efficiency of an apparatus.
In the above types of carbon black production apparatus it is relatively difficult and also costly to produce different carbon black grades. This is due mainly to the fact that various operating parameters must be adapted to one another. On the one hand the fuel and air quantities for producing the fuel gases, and on the other hand the hydrocarbon quantities, as well as optionally the carrier gas and water quantities have to be regulated and matched to one another. If a carrier gas or water and/or water vapor are added, then additional reactions occur with the other components. Thus, with the known construction of a carbon black production apparatus, few carbon black grades can be produced in an economical manner. This is an important disadvantage, because it is desirable to be able to produce the particular carbon black grade which is in demand.
It is one approach to reduce the number of operating parameters which have to be regulated. Thus, there is known a further type of carbon black production plant, in which the same hydrocarbons are used both for producing the heat of reaction and for producing the carbon black. This leads to a significant operational simplification, such as is described, for example, in the U.S. Pat. Nos. 2,643,182 and 2,144,971. However, this simplification does not lead to a rapid adaptation of the operation of the carbon black production apparatus to the production of different carbon black grades. As is known, for producing different carbon black grades it is necessary to adhere to different operating conditions and, in particular, to a specific hydrocarbon to air ratio. Carbon black is always produced in a reducing atmosphere, i.e. with a deficiency of air.
Since for the production of increasingly fine carbon black it is necessary to use an increasingly large proportion of air, the thermal loading of the reactor rises in proportion to the production of finer carbon black grades and therefore limits the range of carbon black grades which can be produced in the same apparatus. However, in the case of inadequate mixing of the two components air and hydrocarbon, the free oxygen introduced into the reactor is not completely combined. As a result, the carbon black quality is degraded.